Band saw



July 19, 1927. A. OBERMOSER BAND SAWv Filed Jan. 13. 1925 Fig.1 l

'S--QFP 'Saws lugs-23 being provided, one on'each @nly fthe inotorYhaving a corresponding guiding .atented July 19,' 1927.

PATENT-OFF .aLl-anar onnnnosnn, or Bananen., annum.

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Application filed January 13, 1925, Serial 11o. 2,212, land in GermanyJanuary 15, 1924.

My invention relates to band saws land :specially tothe means fortensioning and ensuring the correct travel of the saw blade. Hit-hertothe driving motors and the driv ing' pulleys of band saws have beenfixed relativelyto the frame, the putting under tensionof the saw bladebeing eifected by vertical adjustment in a slot formed'in the saw frameof the shaft of the upper pulley for the saw blade, said adjustmentbeing of the motor 3 and-of the pulley 5 as these effected by means of ascrew. As the saw works -at a high velocity vbr-ationl and breakage ofthe saw can easily take place, with this construction.

In order to prevent the vsaw from slipping olf the pulleys, the upperpulley is or the axle bearings thereof are' sometimes inclined by theinsertion of washersrand by clamping with the aid of 'a screw, butaccurate adjustment is diicult.

The present in ention has for its object to Aovercome these drawbacksand with' this object in view, the invention consists in hingsuch amanner that the motor together with the drivingpulley onthe motor shafthangs in the saw blade,` thereby putting the same underjtension by itsweight; If theupper pulley is adjusted vertically, agreater or' lesserinclination is given 'to the motor Vand the driving pulley.`- 'Inthisvmanner the '1nclination of the twopulleys one toanother isVautomatically ensured, the motor' being inclined in `a planethrough-the axes of the shafts of the pulleys.

The other features ofthe invention will be described with reference tothe accom? panying drawing inwhich an embodiment of `the invention `isshown, by ample. v In. the drawing: A

Figure 1 is a side elevation land Figure 2 a, front elevation of 'theband Figure 3 is a section through the sawguard taken along w-b inFigure 2.

Referring to the drawingythe motor 3 is hinged to the saw .frame 1 bymeans of a pivot pin 2 which is fixed inthe base of the saw frame andpassed through arms. or lugs 2 3 provided on the motor, preferably twoside of the motor so Vthat the'motor can oscillate in a vertical planebut not tilt laterally. guide sl'ot 12'is' provided in the frame,

ing the driving motor on the saw frame 1n.

way of ex- Y l f is passed whichfalsopasses through the lugs 16 ofthedoor-like-protecting cover'l'?. Ow-

dog 22 for the purpose of further prevent#- ing lateral tilting of themotor. The drivmembers tend to swing downwardly about the pivot pin 2. Aspring'11, the force of which can be regulated by means. of a screw 13,serves to further regulate the tension of the saw blade. By screwing thescrew downwards, the spring v11 is stressed and the motor 3 is presseddownwards. Consequently thegsaw blade is tensioned.

If the shaft 7 of the upper pulley '6 is l vertically adjusted .by meansof the screw 8 'the shaft 4 and pulley 5 -of the driving motor 3. takeup an inclined position. The inclination of the pulley 5 is regulated inthis manner by ad'usting the inclination ofthe moto'r3, its s aft 4 andthe pullt1 5 so that the saw blade movesonthemi dlel not slip olf thesame. As 'soongas the desired "ofthe rimofthepulleysf and 6 and'doesinclination of 'the motor 3,l of its 'shaft 4 andof-the pulley 5 has'been obtained with l I i the aid of the screw 8, the lclamping-screw 9is tightened. It is therefore no -longer necessary to insert washers orthe like and.

the tension of'thesaw. blade"is'regulated,l notbyinclining thefupperpulley 6 but by inclin-ingthe lower pulley 5.

On the frameV 1 of-the band are castfthrough which a long guide. pin 15:ing to thisv arrangement the door-"like protectingjcover can 'be raisedor lowered. with fre'spect'to theframe. The door-like cover' 'surroundsthe upper part ofthe front edge` 'and also the two sides of the sawblade 'SO I that the blade is completely protected. The door-like.protecting cover is cap-shaped.' The' protecting cover rests uponthelshaft 7 of the upper band saw Vpulley 6, an annular groove 18' beingcut. in the' said-shaftin front los'Y l ofthe pulley 6, the part, 19 ofthe protecting.

cover 17, engaglngwith this annulaggroove so that the'protectingcover'cannot be displaced in thedirection' of. the axis ofshaft 7. The bearing of the'A shaft is adjustably i on shaft 7 and asits hinge pin 15 can move mounted in the verticall slot 10 of the sawframe. As the protecting cover 17 rests upfreely in the lugs 14, thedoor participates in any vertical movement of the shaft 7 of the upperpulley 6 and the distance between the cover 17 "and the saw bladeremains always thesame. Owing to this arrangement, the band saw isalways -covered even when the upper pulleyl 6 is being adjusted vert1-cally and during the adjustment of the pul- .ley the workman does notrequireto pay Y after the protecting cover 17 has been raised and turnedaside. The pin 21 is mounted on the table 24 of the band saw.

I claim:

1. A band saw comprising the combination with the saw frame of a drivingmotor having a shaft on which the saw driving pulley is mounted, saidmotor being hinged to said saw frame so that-it hangs together with thepulley in the band saw, an upper pulley adjustably mounted in a. slot ofthe `frame so as to be capable of adjustment in the vertical direction,for regulating the inclination of the motor and driving pulley withrespect to the horizontal plane, a spring and an adjusting screw forsaid spring arranged between said saW frame and said motor for.increasing the load on the saw blade for tensioning the same.

2. A band saw comprising the combination With the saw frame, of adrivingmotor having a shaft on which the saw drivingpulley is mounted,said motor being hinged to said saw frame so that it hangs together withthe pulley in the band saw, an upper pulley adjustably mounted in aslotl of the frame so as to be capable of adjustment 1n the verticaldirection for regulating the inclination of the motor and driving pulleywith respect to the horizontal plane, a guide surface on the saw frameand a guide sur face on said motor for guiding the motor in the planetraversing the axes of the pulley shafts and preventing lateral tiltingof said motor. I

In testimony whereof I aiiix my signature.

ALBERT oBERMosER.

